Result appears here after you select
{ } How to use
- Paste the token — the three dot-separated parts.
- Select Process.
- Read the decoded header and payload.
{ } How it works
JWT Decoder works on the text you provide. Select Process ▸ and it runs entirely in your browser — nothing is uploaded to a server — then shows the result in the Output panel.
Input
- JWT — paste or type your input in the left panel (use Sample for an example)
Output
JSON — copy it, download it, or switch the Output panel to Tree view to explore it.
{ } Common uses
- See which claims a token carries and when it says it expires.
- Check the algorithm and key id in the header while debugging an authentication problem.
- Confirm a token contains the subject or scope you expected.
{ } Limitations
- The signature is not checked. A token whose payload has been altered decodes just as cleanly as a genuine one, so nothing here tells you a token is authentic.
- No claims are interpreted. exp and nbf are shown as the numbers they are; this does not work out whether the token has expired.
- A JWT payload is base64, not encryption. Anyone holding the token can read it exactly as this tool does, so never put a secret in one.
{ } FAQ
Is my data uploaded to a server?
No. Everything runs locally in your browser — your files never leave your device.
Can I process more than one file at once?
This tool works on one input at a time.
Is this tool free?
Yes — it’s completely free and needs no sign-up.
Does this verify the signature?
No — it only decodes the header and payload for inspection. It never sends the token anywhere.